Electrical relay



Feb, 6, 1940. B. MISHELEVICH ELECTRICAL RELAY 2 Sheets-Sheet 1 Filed Feb. 9, 1958 1J ATTORNEY Feb. 6, 1940. B. MISHELEVICH ELECTRICAL RELAY 2 sneets-shet 2 Filed Feb. 9, 1938 INVENTOR 'Jheleul'a? Benjami HS ATTORNEY Patented Feb. 6;, 1940 UNITED STATES PATENT orrics ELECTRICAL RELAY Application February 9, 1938, Serial No. 189,620

Claims.

My invention relates to electrical relays, and

particularly to relays of the direct current polarized type.

One object of my invention is to provide a relay of this type in which the permanent magnet which supplies the polarizing flux to the polar armature also serves to exert a hold-down torque on the neutral armature when the relay is deenergized to prevent the back contacts of the relay from bouncing open due to vibration or shock. Another object of my invention is to provide a relay the design of which is such that it can be efiiciently operated by means of an energizing winding consisting of a single coil. A further object of my invention is to provide a relay which is suitable for use for railway signaling purposes, and which at the same time requires a minimum amount of s ace.

Other objects and characteristic features of my 0 invention will appear as the description proceeds. I shall describe two forms of electrical relays embodying my invention, and shall then point out the novel features thereof inclaims.

In the accompanying drawings, Fig. 1 is a top 5 plan view showing one form of a relay embodying my invention. Fig. 2 is a frontelevational view of the relay shown in Fig. 1. Fig. 3 is a vertical sectional view taken on the line IIIIII of Fig. 1. Fig. 4 is a back view of the relay shown in Figs. 30 l, 2 and 3.

Similar reference characters refer to similar parts in each or the several views.

Referring to the drawings, the relay in the form here shown comprises a top plate A of 35 suitable insulating material such as a phenol condensation product, which top plate serves as a support for all of the operating parts of the relay. Mounted on the top plate A is an electromagnet B comprising a pair of parallel cores l 40 and 2 connected together at their upper ends by a backstrap 3, and provided at their lower ends with enlarged pole pieces la and 2a disposed on the underside of the top plate. The electromagnet B also comprises a suitable operatingwinding 5 4 which, as here shown, is in the form of a single coil mounted on the backstrap 3. To facilitate making electrical connections with the winding 4, the leads lo and 4b thereof are secured to terminal posts 5 and i3 mounted on the top plate A. 50 A neutral armature 1 is pivotally supported for swinging movement toward and away from the pole pieces in and to on two pivot pins 8 threaded through downwardly extending lugs 9 formed on a non-magnetizable bracket which is fastened 55 to the sides of the pole pieces lw and 2a by means of screws it, as best seen in Fig. 2. A plurality of contact fingers, here shown as two in number and designated by the reference characters H and it, are attached to the underside of the armature l by means of insulating supports l3. .5 When armature l is swung away from the pole pieces in and 2:2, as shown in the drawings, the contact fingers H and i2 each engage fixed contact members Ma and lilo to close back contacts i l---i it; l2--i2o. When armature l is swung 10 toward the pole pieces la and 241,. however, the contacts H-Jlal and l2l2a become opened,

the contact fingers then engage fixed coninembcrs lib and 5217, respectively, to close front contacts ll-llb and l2l2b. Thefixed .11} contact members Ha, i211, lib and I21) are attached to terminal posts l4, l5, l6 and ii, respectively, mounted on the top plate A. Electrical connections to the contact fingers ll and i2 are separately made by means of flexible connectors 58 and iii which are attached at one end to the contact fingers, and at the other end to terminal posts it and 2%, respectively, mounted on" the top plate A. y

A bifurcated pole piece it. is secured to the 25 underside of the top plate A midway between extensions lb and lib which are provided on the pole pieces is and 2a, and pivotally supported intermediate its end-s between the bifurcations of the pole piece 2'4 by means of pivot pins 25 screwed through the bifurcations is a polar armature 26, the ends of which underlie the pole piece extensions i and The armature 26 is arranged to swing toward one or the other of these pole piece extensions, but is prevented from actually touching them by means of non-magnetic stops and 2% fastened to the armature. A contact finger 35 is secured to the underside of the armature 25 adjacent one end thereof by means of an insulating support and a similar contact ringer 33 is secured to the underside of the armature 28 adjacent the other end thereof by means of an insuiating support 36. When the armature 255 is swung toward the pole piece extension. it) 01" pole piece la, as shown in the drawings, the contact finger vi engages a fixed contact 35 fastened to a terminal post 38 mounted on the top plate A, to close a normal contact ii--35, and the contact finger 33 engages a fixed contact 31 attached to a terminal post 38, also 5 mounted on the top plate A, to close a normal contact 33-31. When armature 26 is swung toward the pole piece extension 2b of pole piece 2c, however, the front contact finger 3! then engages a fixed contact 39'to close a reverse con- The fixed contact 39 is attached to a terminal post 40 mounted on the top plate A, and the fixed contact finger 4| is attached to a similar terminal post 42 mounted on the top plate A. The contact fingers 31 and 33 are electrically connected with terminal posts 43 and 44 mounted on the top plate A by means of connectors 45 and 48, respectively. While I have shown only two contact fingers attached to the armature 26 for simplicity in illustrating my invention, it is understood that additional contact fingers may be attached to this armatureif desired.

I The relay further comprises a permanent magnet 5% which is secured at one end to the bifurcated pole piece ,24, and the other end of which extends underneath the neutral armature 1' approximately midway between the pole pieces la and 2a in such a'position that when this armatureis swung away from the pole pieces Ia and 2a; it will be swung toward the permanent magnet 5b, and vice versa. The neutral armature is prevented from actually touching the pole pieces to and 2a, 'or the permanent magnet, by means at nen magnetic stops 51- secured to the armature.

With, the relay constructed in the manner described there are a plurality of paths for the flux due to the permanent magnet. One of these pathspa'sses from the end of the permanent mag net which is secured to the pole piece 2 through the'pole piece 24, right-hand half of polar armatux-e 26, as viewed in Fig. 4, the air gap between armature 26 and the pole piece extension lb, pole piece extension 21, pole piece ia, the air gap-between pole piece la and neutral armature 1. the lefthand half of neutral armature l as viewed in Fig. 2, and the air gap between armaright-hand half ofarmature l as viewed in Fig.

2",and' the air gap between armature I and permanent magnet 58 back to the permanent magnet. A third: one of these paths may be traced from the right-hand end of permanent magnet 55, as viewed in Fig. 3, through the pole piece 24; the left-hand end of polar armature 28, as viewed in Fig. 4', the air gap between armature 26' and pole piece extension 2b, pole piece ex-.

tension 27), pole piece 2a, the air gap between pole piece- 2a and armature l, the right-hand half of armature las viewed in Fig. 2, and the air gap between armature l and the permanent magnet 50 back to the permanent magnet. A fourth path for the permanent magnet flux passes'froin the right-hand end of permanent magnet 5i] as viewed in Fig. 3, pole piece 24, the left-hand half of polar armature 26 as viewed in Fig. 4, the gap between polar armature 2B and extension 2?; of pole piece'2, pole piece extension 21), pole piece 2a, core 2, backstrap 3, core 1, pole piece la, the

air gap between pole piece la and armature l, I

the left-hand half of armature 'l as viewed in Fig. 2, and the air gap between armature l and permanent magnet 58 back to permanent magnet 50'.

There are also a plurality of paths for the flux which is set up by the current flowing in the winding 4. One of these paths may be traced from the left-hand end of backstrap 3 as viewed in Fig. 2; through core l, pole piece la, the air gap between pole piece la and armature l, armature l, the air gap between armature l and pole piecev 2a, and pole piece 2a. and core 2 back to backstrap' 3. Another path for the electromagnet flux may be traced from the left-hand end of backstrap 3 as viewed in Fig. 2, through core I, pole piece la, pole piece extension lb, the air gap between pole piece extension lband polar armature 26, polar armature 26, the air gap between polar armature 26 and polar extension-Qb, polar extension 21), pole piece 211 and core 2 back to backstrap 3. A third path for the electromagnet flux may be traced from the lefthand end of backstrap 3 as viewed in Fig. 2,

through core 9, pole piece in, the air gap betweenarmature and pole piece Ia, armature I, the'air gap between armature l and permanent magnet 59 permanent magnet 5i pole piece 24, the left-hand end of polar armature 255 as viewed I in Fig, 4, the air gap between armature 25 and 3 as viewed in Fig. 2', through core i, pole piece I 2a, theair gap between pole piece in and armature '5, the air gap between armature T and permane'nt magnet be, permanent magnet 56!, pole piece 24, the ri ht-hand end of polar armature 2 6 as viewed in Fig. 4, the air gap between polar armature and pole piece extension lb, pole piece extension Ni, pole piece la, and core I back to baclrstrap 3. 1

The magnitudeand direction of the flux in the varicuspathstrac'ed above will depend, of course, upon the proportioning of, the parts, and the parts are. so proportioned that the neutral armature 1 will be picked up or released according as the winding 4 is energized with current of either polarity or is deenergized. The parts are fur- {ther so proportioned that when winding 4 is energized, the polar armature will swing to one extreme position or the other depending upon the polarity of the current supplied to the winding, and that when the winding 4, is vdeenergized,

polar armature Z'GWill be held, by the flux from the permanent magnet, in whichever extreme position it occupies when the winding becomes deenergized. The parts are still further so proportioned that when winding iis deenergized, the neutral armature l willbe held, by the flux from thepermanentmagnet, and by the force of gravityg in" its deen'ergi'zed position with sufficient force to prevent the back contacts of the relay from bouncing open due tovibration or shock.

It should be pointed out that while in describing my invention I have described the relay as comprising a permanent magnet 5t and a polar armature 26 of magnetizable material, the r lay' can be made to work equally well by constructing the armature 26 out of material which can beperma-nently magnetized and by replacing the permanent magnet 59' with a bar of magnetizable material. In this. latter case the permanent magnet would be magnetized to have consequent poles. That is to say, the armature 26 would be so magnetized that it would have two south poles at its center and a north pole at each end :or two north poles at its center and a south pole ateach "end. The operation of the relay when constructed in this manner will be similar to the operation previously described and this operation need not, therefore, be repeated.

One advantage of a relay embodying my invention is that the permanent magnet serves not only as a means for polarizing the polar armature, but also as a means for providing a holddown torque on theneutral armature when the relay is ole'energized.

Another advantage of a relay embodying my invention is that it readily adapts itself to the use of a single coil for the energizing winding, thereby permitting the relay to be built in a minimum amount of space.

A third. advantage of a relay embodying my invention is that the relay can be constructed with a minimum cost.

Although I have herein shown and described only two forms of electrical relays embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. A relay comprising an electromagnet provided with two pole pieces, a neutral armature movable toward or away from both said pole pieces according as said electromagnet is energized by current of either polarity or is deenergized, a polar armature movable toward one or the other of said pole pieces, said neutral and polar armatures being independently movable about separate axes, and a permanent magnet for polarizing said polar armaturehaving one polemagnetically connected with said polar armature adjacent the mid-pcint thereof and the other pole disposed adjacent said neutral armature on the side opposite to said pole pieces, whereby said neutral armature comprises a part of the flux path for the polarizing flux from said permanent magnet. 2. A relay comprising an electromagnet provided with two pole pieces, a neutralarmature movable toward or away from both said pole pieces according as said electromagnet is energized by current of either polarity or is deenergized, a polar armature movable toward one or the other of said pole pieces, said polar and neutral armatures being independently movable about separate axes, and a permanent magnet extending between said two armatures for polarizing said polar armature and having one pole disposed adjacent the mid-point of one armature and the other pole disposed adjacent the mid-point of the other armature.

3. A relay comprising an insulating top plate, two parallel cores mounted in said top plate and provided on the underside of said top plate with enlarged pole pieces, a backstrap connecting the upper ends of said cores, a winding for setting up a flux in said cores, a neutral armature mounted for swinging movement toward and away from said pole pieces, a bifurcated pole piece secured to the underside of'said top plate, a polar armature pivotally supported between the bifurcations of said bifurcated pole piece for swingingmovement toward one or the other of said first mentioned pole pieces, and a permanent magnet secured at one end to said bifurcated pole piece and having its other end disposed adjacent said neutral armature on the side opposite said first-mentioned pole pieces.

4. A relay comprising an electromagnet provided with a pair of pole pieces, a first armature pivotally supported for swinging movement toward or away from said pole pieces according as said electromagnet is energized by current of either polarity or is deenergized, and polarized means including a second armature pivotally supported intermediate its ends for swinging movement toward one or the other of said pole pieces and a fixed member having one end disposed adjacent said second armature at'its center and the other end disposed adjacent said first armature in such a position that thepolarizing flux will pass through said first armature and act as a means to urge said first armature away from said pole pieces when said electromagnet is deenergized.

5. A relay comprising an electromagnet pro vided with a pair of pole pieces, a neutral armature pivotally supported for swinging movement toward or away from said pole pieces according as said electromagnet is energized by current of either polarity or is deenergized, a polar arma- 

